Partial oxidation reactions are important in the production of a variety of chemicals and fuels. These reactions are typically highly exothermic and often have significant adiabatic temperature rises. Further these reactions often generate free radicals. The selectivity of these reactions is very sensitive to temperature, such that reactors undergoing excessive reaction develop hot spots that lead to reactant ignition and/or a product selectivity that shifts toward total oxidation.
To address these problems, reactors are commonly designed or operated: (i) using small diameter reactor tubes with high surface to volume ratios for higher heat transfer rates, (ii) by reducing the reaction rate per unit volume inside the tubular reactor, such as by placing inert material into catalyst beds, (iii) using sub-stoichiometric levels of oxygen to limit the extent of reaction, (iv) by introducing inert gases to the reactant fluid to serve as a thermal sink for the exothermicity of the reaction, and/or (v) by introducing inert gases to dilute combustible gas concentration to below the explosion threshold. These approaches are used to lower the rate of reaction per unit volume, in order to maintain the temperature inside the reactor tube within a desired range. However, these approaches also increase inefficiencies in reactors, such as low reactant per pass conversion, and/or high cost and energy requirements.
Therefore, there is a need for safer and/or more efficient reactors.